Scientists are about to use supernova cosmic rays to peer inside the most dangerous room in the world: Fukushima

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One of the intrinsic problems with shielding a nuclear reactor is that, if something goes wrong, the walls will keep you out just as effectively as it keeps killer radiation in. That’s of course a worthwhile trade-off to make, but it leaves us with an interesting problem. If we absolutely must see inside the reactor at Fukishima Daiichi (and we must), how can we generate rays powerfully enough to enter the core on one side and exit through the other? The humbling answer is that we can’t — so, instead scientists are turning to nature’s own ultra-high-power cosmic rays, generated by supernovae and galactic nuclei, to produce what could be described as an interstellar X-ray machine. The result is a process called muon tomography, and after months of planning it finally seems to be going forward under the banner of the Los Alamos National Laboratory. Researchers are about to get a look [PDF] inside the most dangerous room in the world.

Muons are fundamental particles much like electrons, and scientists have actually been using them in imaging for some time. Muon tomography first came to prominence via the Great Pyramid of Giza which, as you probably know, is constructed from enormous stone blocks. These thick walls stymied any technological search for remaining hidden chambers, and presented essentially the exact same problem as the Fukushima reactor core. Physicist Luis Alvarez turned to muons as his interrogating particles, since he knew they could move through the pyramid walls quite easily. The rate at which muons that enter the walls managed to come out the other side corresponds to how much stone they have passed through. A higher percentage of muons making it through the pyramid meant they passed through less stone — which meant an empty chamber. Alvarez’ experiments finally ruled out the possibility of new hidden room.

At Fukushima, cleanup crews hope to use a more advanced version of the technology that doesn’t just measure the rate at which muons are transmitted through the core, but the angle as well. See, the reactor core is mostly empty space at this point, and the resolution of so-called muon stop tomography is too low to show the positions of individual objects in a room. However, the incoming angle of a muon is sometimes different from that its outgoing angle, and researchers can walk that difference back to calculate what it objects could theoretically cause such a deflection. Any one muon deflection could be caused by a number of different internal structures, but by cross-referencing their paths the researchers can narrow the possibilities to one.

The proposed tracker setup will look straight through the centre of the core in an attempt to locate the biggest pieces of debris and quantify the damage inside.

Muons are a product of cosmic rays (protons) hitting gaseous atoms in the upper atmosphere and creating incredibly powerful debris in the form of elementary particles. Note that this is a very, very inefficient way of looking inside something, since every data point is essentially a cosmic event. The research team doesn’t get to decide when their next interrogating muon might arrive. The picture will resolve slowly, showing the general layout of the reactor core in radioactive pointillism. These muons are basically impossible to create artificially, since their production requires energies that even nuclear weapons can’t reach.

Note that the resolution on this technique is very low, though the Fukushima tracker will be much higher fidelity

This effort was first proposed some time ago, but it’s only now that Los Alamos National Laboratory seems to be making real forward progress with funding and execution. The team wants roughly $1 million in funding for “Phase 2″ of their round-up, but eventually projects a need for a full $4 million from each of the Japanese and American governments. This could even prove to be a good long-term investment for both nations, as LLNL wants to apply any muon-tracking technology it develops to ongoing reactor safety. Muon tomography is already used to search for nuclear material in shipping containers — why not working nuclear reactors? Dense and highly energetic samples (like weapons- or reactor-grade fissile materials) are perfectly suited to muon interrogation.

The LLNL team hopes that this could become a standard part of reactor maintenance routines, incorporating some of the universe’s most energetic particles into regular nuclear maintenance routines. That’s pretty cool all on its own, but if it helps image the level of destruction inside the Fukushima reactor core it could also help undo one of the industry’s greatest mistakes.

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We could always get Paris Hilton and the Kardashians to go take a look for us

Bilal Mahmood

or send obama

GMarsack

I’d like to have Justin Bieber and Miley Cyrus give it a try also.

anders bjørnø

I’d also like to nominate Kanye West and Drake with a side-runner of Lil Wayne if possible.

Mike

One of the industry’s greatest mistakes? Fukushima is a stellar example of everything in the nuclear industry going RIGHT. This was literally a worst-case scenario, and they still managed to prevent a full-scale meltdown. And that with half-century-old technology.

Fukushima, properly understood, should be used as an example as to why modern nuclear reactors should be trusted.

Ivor O’Connor

Yep. Just wait till one of the hundred reactors in the USA go horribly wrong. We’ll be wishing we got rid of nuclear power when we could have.

cjl

One did. It was called Three Mile Island. It killed nobody and didn’t significantly contaminate the surrounding area. Nice try with the doomsday claims though.

Ivor O’Connor

So you think that’s as bad as it gets?!

cjl

That’s just about as bad as it gets with a modern, reasonably safe design. If you start intentionally looking for bad designs (which were never in operation in the US), it gets as bad as Chernobyl, but that failure mode is not possible on any US nuclear plant. Any disaster sufficient to breach containment on a US nuclear plant will cause vastly more damage than the breached nuclear plant will (similar to how the tsunami caused far more damage than Fukushima did).

Ivor O’Connor

So you are of the opinion the tsunami caused far more damage than the nuclear plant. I guess it depends on how you look at damage.

So though their nuclear plant is pretty much the same as ours it could never happen here. America is such and exceptional country nothing could go wrong.

What will happen to our nuclear plants? Will they be decommissioned like the two at San Onofre because they are too expensive to keep repairing. Or will they die horrible deaths like Chernobyl and Fukushima did.

And are there any possible scenarios where they don’t end up costing tax payers hundreds of billions of dollars in clean up fees?

Barry

I think that the guys running TEPCO should get the first look! Anyone concerned about being radiated with contaminated after eating Pacific Ocean fish and seafood may want to look into doing a radiation and heavy metals detox with the natural mineral called zeolite that is proven to safely remove both radiation and heavy metals from the human body! For more information do a search for the single word Zeolite.

http://www.oh-ya-I-have-one.com Jared Haer

Barry I think your claims of zeolite being able to “detox” heavy metals and radiation are completely unfounded. I think you are just trying to create a buzz to move a product with no care for the buyers health and well being.
Where in medicine has zeolite ever been used to removing heavy metals from a human being? Please cite one study from a major medical journal.
Barry I think you are a pusher of snake oil.

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